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Warning/Advisory Criteria

Type Criteria
Winter Storm Warning

Snow: 4-6" in 12 hours, or 6-8" in 24 hours. Click each link to see maps that give specific criteria for each county.
Ice Accumulation: 1/4 inch or more
Also can be issued for hazards judged to pose a threat to life and property.

Winter Weather Advisory

Snow: 2-4" in 12 hours. Click link to see map that gives specific criteria for each county.
Ice: Any accretion
Also can be issued for hazards which cause "significant inconvenience" and warrant extra caution.

Blizzard Warning Sustained or frequent gusts greater than or equal to 35 mph AND considerable blowing/drifting snow frequently reducing visibilities to less than 1/4 mile
Wind Chill Advisory Wind Chill values less than or equal to -10° F for 3 hours or more with wind speeds greather than 5 mph
Wind Chill Warning Wind Chill values less than or equal to -25° F for 3 hours or more with wind speeds greather than 5 mph
Frost Advisory Issued in conjunction with a killing frost only (sufficient to end the growing season in fall, or delay it in the spring); how far low temperatures are below freezing at the ground, and for what duration are the factors determining if it is a killing frost.
Freeze Warning Issued in conjunction with temperatures forecast to be 32° or below for a significant amount of time (with or without frost)
Dense Fog Advisory Issued for widespread fog reducing visibilities to 1/4 mile or less.
Heat Advisory Heat Index greater than or equal to 100° F and less than 105° F for 2 hours.
Excessive Heat Warning Heat Index greater than or equal to 105° F for 2 hours.
Wind Advisory Winds of 31-39 mph sustained for 1 hour, or between 46 and 57 mph for any duration
High Wind Warning Winds 40 mph or higher sustained for 1 hour, or 58 mph or greater for any duration (non-convective)

 

What to Report and How

To report severe weather, call
1-304-746-0180, email us at
rlx.storm@noaa.gov,

Facebook:  https://www.facebook.com/NWSCharlestonWV

Twitter:  #nwsrlx



 

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National Weather Service
400 Parkway Road
Charleston WV 25309
(304) 746-0180
rlx.webmaster@noaa.gov
Page last modified: April 18, 2013

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